Benjamin Graham taught an investment class at the Columbia University business school for 28 years. If you had been a student in Graham's classes during the early 1950s, your textbook, Security Analysis, would have been written by Graham himself, along with David Dodd.

You may have also met a few interesting students by the name of Warren Buffett, Bill Ruane, Tom Knapp, and Walter Schloss. Each of these men would go on to manage investments in one form or another. Buffett and Schloss both started investment partnerships. Buffett folded his partnership in 1969, but his partners were given the opportunity to receive shares of a struggling textile manufacturer named Berkshire Hathaway BRK.B. Ruane and Knapp started firms that manage public mutual funds.

In 1984, Buffett returned to Columbia to give a speech commemorating the 50th anniversary of the publication of Security Analysis. During that speech, he presented his own investment record as well as those of Ruane, Knapp, and Schloss. In short, each of these men posted investment results that blew away the returns of the overall market. Buffett noted that each of the portfolios varied greatly in the number and type of stocks, but what did not vary was the managers' adherence to Graham's investment principles. The investment principles taught by Graham at Columbia served his students exceptionally well, and it is difficult to overstate the influence Graham had on the field of professional stock analysis. The good news is that Graham made the same principles easily accessible for ordinary investors by writing the classic book The Intelligent Investor.